The invention concerns a floating foundation and a method for its manufacture.
In particular for erecting wind power plants, but also for anchoring other structures in the ocean, for example, marine navigation marks, drilling platforms and the like, numerous variants of floating foundations have been proposed. They are based on buoyant bodies which, in the immersed state, provide buoyance that is significantly greater than the weight of the structure and of the load to be carried wherein the buoyant bodies are anchored by cables or chains to the ocean floor in the submersed state.
For example. GB 2 378 679 discloses such a floating foundation for a wind power plant. It is comprised of several buoyant bodies that are connected by means of radial steel beams to the tower. In plan view, the steel beams are arranged in crossing arrangement and are not connected to each other.
When bending forces are acting on the radial steel beams of the structure, they cause high bending moments.
WO 2007/096680 proposes a modified construction with a floating foundation that is quadrangular in plan view. The buoyant bodies that are arranged at the corners are connected to each other by tie rods and compression bars to a three-dimensional support structure. A central large buoyant body supports a tower that is braced by inclined cables to the outwardly positioned buoyant bodies.
Even though in connection with this structure it is said that it is subjected to only minimal oscillations, a high constructive expenditure is required.
U.S. Pat. No. 7,156,586 B2 proposes a floating support structure that has arms extending radially away from a tower. They are provided at their ends with buoyant bodies. For stabilizing the tower position, inclined cables are tightened between the buoyant bodies and the tower.
At the central base of the tower, stress concentrations result that may cause problems; but, at least, they will increase the construction expenditure.
EP 1 288 122 A2 proposes a floating support structure in the form of a massive floating platform with several chambers that, like a diving bell, are filled with air and therefore can be utilized to produce buoyance.
The erection of such a floating foundation requires a high material expenditure.
Moreover, EP 1 876 093 A3 as well as DE 10 2008 003 647 propose floating support structures in which the buoyant bodies are provided on ends that extend radially away from a central structure.
It is the object of the invention to provide a concept with which ire a simple and reliable way floating support structures can be produced.